Novel ring expansion routes are proposed to synthesize 8,9,13,14-disecosteroid molecules that are related to estrone and zearalanone hormones. The key step in one route is a four-carbon ring expansion that is related to the siloxy-Cope rearrangement. The other route uses both siloxy-Cope and acid catalyzed two-carbon ring expansions to build up the large ring system. Experiments are also described that probe the mechanism of the siloxy-Cope rearrangement by following the stereochemistry of optically active systems and by generating related diradicals from azo precusors.